Electric transformer.



Patiented May 7, l90l.

m, PIGNOLET. -E-L-EGTRIC IRANSFORMEB.

(Application med se fllo, 1898.)

-4 I TORNEY 2 Shanty-Shoot I.

INVENTOR P7710281 (No llodul) WITNESS S: cm W Patented may 7, I901.

- L m. PIBNOLET. ELECTRIC TRANSFORMER. 7

(Application filed Sept. 10. 189B.)

2 sham-shut i) (No Model.)

INVENTOR Louis M PZ iWqfeZ I BY A ORNEY m: can: PETERS co VHOTO-LIYHQ,WA5HINGTON. ov c.

V UNITED STATES PATENT OFFICE.

LOUIS M. PIGNOLET, OF ORANGE, NEIV JERSEY.

ELECTRIC TRANSFORMER.

SPECIFICATION forming part of Letters Patent No. 673,567, dated May '7,1901.

, Application filed September 10, 1898. Serial No. 690,640. (No model.)

To all whom it may concern:

Be it known that I, LOUIS M. PIGNOLET, a citizen of the United States ofAmerica, and

a resident of Orange, in the county of Essex .and State of New Jersey,have invented certain new and usefullmprovements in anElectrio-Transformer Regulator, of which the following is aspecification.

My invention relates to an electric transformer and its adjuncts, all soconstructed that by the movement of a switch manually a single coil at atime or two or more coils at a time are cut intoor cut out of circuit ofthe secondary element of the transformer, and yet all thisisaccomplished with but a comparatively few connections with the coilsthemselves.

The object'of the invention is to remove the difficulty, to a greatextent, of soldering or otherwise making electrical connection betweenthe wire of the secondary coils and the wires leading to any givenswitch for regulating the number of secondary convolutions in or out ofcircuit. Usually to cut in one coil at a time in a secondary having,say, fifteen coils would require about thirteen joints between the wiresof the coils and the wires that go to the switch, whereas with myinvention I would require only four joints and yet be able to secure thesame results.

In order to carry out my invention, I provide the usual primary andsecondary coils constituting the transformer. The secondary is dividedinto sections or groups of coils, each group containing as many coils asthe other, although this is not absolutely essential, for there may beone coil by'itself to be used as the first coil and to be thrown intocircuit when it is desired to have a transformer that will give a verysmall voltage at the beginning of the current. I provide also a certainnumber of extra secondary coils, or coils that are for the purpose ofcarrying out my conception of reducing the number of joints. The numberof extra coils is one less than the number of coils in any one of thegroups into which the secondary coil is subdivided. For example, if thegroup has four coils the number of extra coils is three. The groups ofcoils are all connected consecutively in series with one another; butthe extra coils are not electrically connected to the other coils, whichwhile in contact with them.

are in groups, although they are connected to each other in seriesconsecutively, reference being had in both cases to the omission of theswitch, which serves to vary the connections in a variety of ways in thefollowing style: The groups of coils which may be called the principalor main coils are accompanied by a set of contact-bars for the switch tomove over These contacts are respectively connected to the respectivegroups of main coils, so that if there are eight groups there are ninecontacts. The extra coils are accompanied by groups of contacts, and ineach group there are several contacts, but always one more than thenumber of extra coils, and the number of contacts in each group is onegreater than the number of extra coils. A switch connects the contactsthat are provided for the groups of main coils with the contacts thatare provided for the extra coils. As the switch moves from one maincoilcontact to the other and along the maincoil contacts it includes intothe circuit, first, a certain minimum number of main or extra coils, andthen successively a single coil at a time, if the graduation is to be sosmall, or any given small number of coils, so that the regulation may beas gradual as could ever be desired in practice.

In commerce I employ this invention for regulating the heat electricallyapplied to a pair of surgical forceps and for certain other purposeswhere regulation is desired and yet where the objection arises to thegreat number of joints, as above pointed out.

Figure 1 is a diagram of an electrical transformer and of the means forregulating the number of secondary coils in circuit with the terminalsof the device. The diagram illustrates also the principle of mechanicalconstruction. Fig. 2 shows substantially the same thing, with theimportant exception that the mechanical construction is such that theinstrument is much more compact, a very desirable feature in regulatingdevices. Fig. 2 is a partial side elevation of that in Fig. 2. Fig. 3shows in diagram a modification and serves to illustrate the generalprinciple underlying the method of electrically connecting up the coilsand contacts, howsoever large or small may be the number of coils in thesecondary.

Referring to Fi '1, a is the primary ecu or an electric transformer. bis a single" coil of the secondary coils of the same transformer. 0represents a group of three coils of the secondary of said transformer.d is a second group in series circuit with the coils b and c, andfis theterminal of the coil b and forms the terminal of. the secondary of thetransformer, whose purpose, as represented, is to reduce theelectromotive force. g is the other terminal ofthe secondary coils ot'the transformer. The other terminal of the coil 6 is connected to thefirst of a row of contacts h, 'i, andj. The joint k is the one betweenthe wire land the com monterminal between the coil b and the coils c.The wire Z connects said joint to the contact h. Z is a wire that joinsthe terminals of the coils c and d to the next contact 71. Z" is thewire thatjoins the contactj to the common terminal of the coils.

d. A and B are single coils acting as secondary coils to the sameprimary coil a, but are not in series nor connected otherwise to thesecondary coils b, c, and (1 except by means of a certain switch undercertain circumstances. C is a switch which is pivoted at its center atD. One end moves over and in contact with the contacts h, i, and j. Theother end moves over and in contactwith three times-as many contacts E,F," G, H, I, J, K, L, and M, arranged in the path of the said switch.When one end of the switch O is "in contact with the contact h, theother end may be in contact with any one of thethree contacts E, F, orG, While the switch O is in contact with the next contact, '5, the otherend may be in contact with any one of the contacts H, I, or J Also whenthe contact j is in contact with the switch 0 thelatter isin contactwith one of the contacts K, L, or M.- The three contacts E, F, and G areconnected, respectively, by the condnctors N OP with the terminals ofthe coils A and B. The contacts H, I, and J are likewise connected withthe terminals of the coils A and B through the conductors in order Q Nand RD and S P. The terminal E is connected to the terminal g of thewhole device. V

The operation and results, in View of the above construction andelectrical connections, are as follows: When the switch 0 moves overthe'successive contacts E F G, &'c;., there is in circuit between theterminals f and g first one coil of the secondary, then two coils, andthen three, then four, and st; on up to the maximum number. This willbecome apparent by tracing the currents. Let the switch G touch thecontact h, so that one end is on the first terminal contact E. Thecontinuous circuit through the appara tus is therefore from the!terminal f to one end of the 'coil b, through the said coil to the jointis, through the wire Z to the contact h, to and through the switch O tothe contact E, through the conductor E, and finally to the terminal g,and as a consequence there is but one coil of the secondary in circuitwith the terminalsfand g or the regulating instrument. When the switch 0comes to rest upon the contact F,the circuit is from the terminal f tothe coil 1), to the contact h, through the switch 0 to the contact F,through the conductor O to the coil A, through the conductor N to theterminal g, and hence there are two coils of the secondary in circuitbetween the terminals of the instrument. One of the coils is a main coilb, and the other is one of the extra coils, B. Theyare in series witheach other, so that the electromotive force of the current is increasedover what it was when but the coil 1) was in circuit. When the switchmoves on and comes into contact with the next contact, G, the circuit isfrom thecontact or terminal f, through the coil 1), through the switch Cto thecontact G, throughthe conductor P, through the coil A andpoil B,through the conductor N, and finally tothe terminal .9. Three coils aretherefore in circuit. When the switch moves on and comes intocontactwith the contact I-L'it has passed to the contact 71. In view of theconnections already described there are four secondary coils incircuit-namely, the coil b and the group of coils c. 1 could alsc showthat as the switch 0 moved farther and farther to the remainingcontactsthere would be in circuit first five, then six, then seven, then eight,and then nine; but as the connections are all shown and as severalcircuits have been traced by reference-letters itis thought unnecessaryto trace any more circuits-for different positions of the switch 0.

By counting the number ofjoints that have to be made between the end.joints, which cannot properly be called joints because merelycontinuations of the wires of the coils, itwill be noticed that thereare but threejointsnamely, at 74;, at the end ofthe wire Z, andat theend of the wire O-and yet I am able by such a few joints to throw intocircuit first one coil, then two, then threeythen four, and soon all theway up totencoils.

Fig. 2 shows especially how the construction may be made more compact byhaving the contacts h ii and the other contacts considered as adifferent set E F G H, &c., arranged concentrically to each other. Theci rcle T is a handle for turning the switchO.

Otherwise the construction is the same as described by reference to Fig.1, except that some of the wires are longer or shorter or eX- tending indiflerent directions; but no fur; ther description is necessary to thoseversed a a Fig. 2 shows how the switch O bridges the contact j withouttouching it. I have thus far described only the actual construction andelectrical connections ofapparatus for carrying out the invention; but

I have not set forth the general principles of construction so that anyone versed in the art could design instruments of di'fterent capacityanddegrees of regulation. Hcwever, by

understanding my description of Fig. 3 in for regulation of smallcurrents or for large addition to the information regarding Figs. 1 and2 I believe that any one may design the device to suit any useas, forexample, either electric light and power plants. At the same time Fig. 3illustrates a modification where the first group into which thesecondary coil is subdivided is not a single coil, but four coils.

I will use reference-numerals, as they will make the description seemmore systematic.

1 represents a primary coil in circuit with the alternator 2 for sendingan ind ucing-ourrent through said coil. The main coil of the secondaryis divided into two general sets the main coils and the extra coils. Themain coil is divided into groups which are in series with one another,and the number of coils in each group may be chosen at random oraccording'to the total number of coils in the secondary or according tothe degree of gradual regulation to be effected; butin all cases thenumber of coils in each group should be equal. In the casein hand thegroups are three in number and there are four coils in each group. Thefirst group is indicated by the second by and the third by 3'.

The individual coils of each group are numbered in the first. group 4-.5 6 7, in the second group l, 5", 6", and 7, and in the third group 4' 56 7". As there are three groups there is that number, plus one, ofcontacts, which are numbered 8, 8", 8', and 3. This is always the case,as there should be one more contact provided than there are groups.There may be, but not necessarily so, an exception, as illustrated, forexample, in Figs. land 2. Here there are three groups I), c, and d, andyet there are butthree contacts h ij. The exception occurs when there isbut one coil 1) in the first group, and therefore the current has thevoltage at the beginning of only one volt,if each coil represents avolt; but usually about four coils should be the minimum number of coilsin the secondary group 3, and then, as hereinafter explained, the firstcoil which is in circuitis one of the extra coils. An engineer willunderstand when it is necessary to have one more contact than groups.Having marked off the groups of coils 3" 3, the constructor shouldsolder a wire 9" to the wire of the secondary between the first andsecond groups 3' and 3 and lead it to and electrically connect it to thesecond contact 8". The next wire 9" should join the secondary betweenthe second coil 3" and the third coil 3 to the third contact 8. One endof the secondary considered as a whole or one terminal of the group 3should beconnected by the wire 9 to the first contact 8 and also to theterminal of the whole apparatus at 10. The other end of the secondaryconsidered as a whole or the other end of the group 3 should beconnected by the wire 9" to the lastterminalcontact8. Thesemaybetaken asthe rules for subdividing the secondary coil'into groups and forconnecting them up tothe contacts forming the first pair or set' ofcontacts. They are shown lying in a straight row; but this is forsimplicity of illustration, as in practice the arrangement wouldpreferably be as shown in Fig. 2. there are three groups of coils, thereare two joints, as at the ends of the wires 9 and 9'. The next pointisto know the number of cxtra coils that should be employed. The rule isthat there should be one less than the number of coils in any one of thegroups. Accordingly there will be noticed the coils 11 11 11". These aresecondaries of the same primary coil 1; but they are not contin-nationsof the main secondary coils 3 3" 3". The second set of contacts isdetermined by providing for each contact 8 or 8 or 8 or 8 four contacts.The first four are numbered 12, 12", 12, and 12. The second set is ]31313 13". The third set is 14 14114! 14. The fourth set is 15 15" 15" 15.The four terminals of the extra coils are connected to the four contactsof each group; but it should be noticed that the first contact 12 isconnected to the last terminal of the last coil 11 and also to theterminal 10 of the instrument. More generally, the connections betweenthe extra coils 11 11" 11 and the first set of contacts 12 12" 12" 12 issuch that as the switch 16 moves in contact with the contact 8' and withsaid first set of contacts the circuit will be first a short-circuitingof the instrument with no current, then the inclusion of a single extracoil 11 then two coils 11 and 11", and then three extra coils 11, 11",and 11, and a further movement will throw into circuit the four maincoils 4., 5, 6, and 7, but before the said four coils are in circuit theswitch 16 has moved to the next contact 8". By omitting the wire 17,which connects the first contact 12 to the terminal l0,the instrumentneed not be shortcircuited at the first terminal or contact 12.

A more general rule more easily understood now that the figures have allbeen referred to is that the secondary should be divided into any givennumber of groups with an equal number in the respective groups and thata number of extra coils should be added as secondaries, but they shouldnot be connected directly to the said groups and only by means of aparticular switch. Each group of main coils should be accompanied by onecontact, necessarily made of a definite length, because each of saidcontacts should be accompanied by as many contacts as there are extracoils, plus one, while the number of extra coils should be one less thanthe number of coils in any group of main coils. The

1. In an electric transformer, the combination of groups of principalsecondary conductors wound into equal numbers of coils and permanentlyconnected consecutively in series circuit with one another,and havingtheir terminals connected respectively to different contacts forming afirst set of the same'numv her as there are groups plus one, an extrasecondary conductor wound into as many coils, less one, as there are inany group of principal coils, the extra coils being permanentlyconnected consecutively in series circuit with one another, a second setof con- ,tacts for-med of as many groups as there are contacts in thefirst set, and each group having as many contacts as there are extracoils plus one, conductors connecting the terminals of the extra coilsto the contacts of each group, and a switch movable successively overand in contact with both sets of contacts for the purpose set forth.

2. The combinationof electrically-separated sets of transformer-coils,concentric rows of contacts, a rotary switch for connecting the rows ofcontacts in a predetermined order, conduotorsconnecting one row ofcontacts to the terminals of groups of coils, of the one set of coils,and other conductors connecting the other row of contacts to'difierentcoils of the other set of coils.

Signed this9th day of September, 1898.

LOUIS M. PIGNOLET.

Witnesses:

WILLIAM J. BARKER, J. E. COLEMAN.

